[Mailman-Developers] Mailman3- postorius_standalone Issues

[Fotso Fono]

Hello, i am trying to set up Mailman3 everything has been moving on well. i
ran the command "python manage.py runserver" in postorius_stanalone. when i
access localhost:8000 and error pops on the terminal saying "no module
middleware found" and an error page is displayed on browser. I tried
getting the root of the problem.
In postorius_stanalone in the MIDDLEWARE_CLASSES,
"postorius.middleware.PostoriusMiddleware"  seems to be the one causing the
the problem. Please is there any solution to this or have i done something
wrong?? I am new to mailman. thanks in advance